The subject matter disclosed herein relates to gas turbine engines and, more particularly, to a load pin for use in conjunction with a cutout formed in the bottom of a square base vane to lock the vane in place within the compressor case of a gas turbine engine.
A number of square base stator vanes or airfoils are typically loaded circumferentially into a compressor casing through a cutout in the casing. Due to the aerodynamic loads on the airfoils, the stators are commonly loaded into the casing in the counter-clockwise (CCW) direction, as viewed forward looking aft (FLA). Since these stators are essentially stacked up circumferentially without any of the stators being locked in place within the casing by any separate physical means, the cumulative aerodynamic load also increases in the CCW direction. Currently, there is no limit to the number of vanes that load up in either half of the casing. That is, all of the stator vanes in the upper casing half will load up on the vane at the upper casing half left hand joint (as viewed FLA). Similarly, all of the vanes in the lower casing half will load up on the vane at the lower casing half right hand joint (as viewed FLA). Strain gage test data on the stator vanes shows that the vibratory responses are highest at the vanes with the highest cumulative load. For the upper half of the compressor casing, this is the vane at the left hand joint between the upper and lower casing halves (9 o'clock position, as viewed FLA). The lowest vibratory responses are at the vanes with the lowest cumulative load. For the upper half of the compressor casing, this is the vane at the right hand joint between the upper and lower casing halves (3 o'clock position, as viewed FLA). Furthermore, it has been shown that the vibratory response levels increase linearly in the CCW direction.